[IOT HUB message twin change events routing to Event hub] consumer receives full desired properties on change of a single desired property on cloud

[amit12cool]

• Package Name: azure/event-hubs,
• Package Version: 5.9.0
• Operating system:
• [X ] nodejs
  • version:
• [x] browser
  • name/version:
• [x] typescript
  • 4.9.5:
• Is the bug related to documentation in
  • [ ] README.md
  • [ ] source code documentation
  • [ ] SDK API docs on https://docs.microsoft.com

Describe the bug I have a event hub consumer in typescript with blob check point store. On changing or adding a new property in desired twin from cloud I get the full desired property object on my event hub consumer client.

For example:-

Lets say we add test key in desired property from cloud.

desired: {
"test":"123", // this is added
"test2": "456"
}

The event received on event hub consumer client is as below:-

desired: {
"test":"123",
"test2": "456"
}

To Reproduce Steps to reproduce the behavior:

1. Subscribe to twin change events from iot hub to event hub endpoint.
2. Change desired property of a device in cloud.
3. Observe full device desired properties event is received on the event hub consumer client.

Expected behavior Only the changed desired property data should be received in the vent hub consumer client event i.e.

desired: {
  "test":"123",
}

Refer issue filled on event hub repo Here which guided me to file this issue in this repo.